The Bureau of Safety and Environment Enforcement new well design regulations address annular pressure buildup (APB) mitigation options. The use of a rupture disk is one option to relieve APB, which is quite common in deep-water wells. Manufactured to fail at a specific pressure difference with a very tight tolerance, rupture disks are installed in the casing walls to protect either the external or internal casing string. A rupture disk can be installed in a casing string interval, which is externally cemented. The rupture disk fails when the internal-external pressure difference exceeds its rating. The internal APB may be relieved through fluid movement into the pore space, micro-channels or fractures in the external cement section. Once the rupture disk fails in this situation, the rupture disk is identified as open (vented/leaked). Simulation of rupture disk failure effects on annular fluid expansion (AFE) analysis and casing load analysis can provide valuable information to assist wellbore tubular design.